What do you believe? Are you prepared to open your mind to new facts? Cognitive psychologists tell us that most people cling to what they already believe and are so averse to changing their minds that new facts only make them cling to their old beliefs even MORE stubbornly. So, are you prepared to open your mind?
As of 2016, millions of women do not believe that estrogen therapy reduces breast cancer risk. In fact, they feel sure that it increases the risk. But new research confirms lots of old research. The answer to the question in the title is TRUE.
Why do so many women hold mistaken beliefs about estrogen, mistakes that cause them to avoid taking estrogen when it is such a beneficial hormone and could save their lives? There are three main sources of misinformation:
1) Misunderstood findings from the Women’s Health Initiative (WHI), a large study released in 2002.
2) Misunderstanding estrogen therapy for women who've had a hysterectomy versus those who haven't.
3) Misunderstanding anti-estrogen treatments for breast cancer.
EmpowHER has previously focused on how so many people were misled by reports of the WHI findings, so we will only briefly discuss it here.
The WHI was really two studies. The first to be reported was the study of women who had a natural menopause and still had a uterus. These women needed to take estrogen PLUS a second progesterone-like hormone to protect the uterus from developing cancer. The hormone chosen by the WHI is called Prempro and the progesterone in this pill is unusually powerful at suppressing the effects of estrogen — including all the good effects.
There are many forms of menopausal hormone therapy on the market and the findings for Prempro do not apply to other forms. But the media did not realize or report this fact. When it was found that women using Prempro were at greater risk for heart attacks, strokes and breast cancer, people panicked and abandoned any and all forms of menopausal hormone therapy. They threw out the baby with the bath water.
In 2004, the WHI reported the findings of their second study of women who had a hysterectomy and who took estrogen-only (ET). This study found only one health risk (as long as the women were not over 60 when they started ET), and that is a slightly increased risk of VTA (a blood clot in a vein). Even that risk is essentially eliminated by using an estrogen gel or skin patch instead of taking a pill.
WHI follow-up results published in 2011 found important health benefits of ET. Did women and doctors then start using ET in droves? No, they did not. Why? Their pre-existing fears trumped new information. Our study estimates that thousands of women have already died and thousands more will die because unwarranted fears keep them from using ET.2
The second cause of women’s avoidance of ET is their incomplete understanding of the relationship between estrogen and breast cancer. That relationship is extremely complex and hard to understand. Many women have heard that breast cancer is widely treated by taking an anti-estrogen (e.g. tamoxifen or an aromatase inhibitor).
Women also hear that many breast cancers contain estrogen-receptors. It seems logical to conclude that estrogen must promote the growth of breast cancer cells, but that is not the whole story. Very few women know that estrogen also kills breast cancer cells!3
We promise a new article on the Ahah section soon that will go into more detail about the complex relationship between estrogen and breast cancer. We want to leave you with this fact from the WHI study of women using ET:
In the three-and-a-half-year follow-up of ET users, it was found that ET significantly reduced the risk of developing breast cancer.4
Our take-away message is that beneficial effects of estrogen replacement therapy occur in women with hysterectomies who start ET prior to age 60 or within 10 years of menopause.
Are you able to believe it?
Reviewed February 17, 2017
by Michele Blacksberg RN
Edited by Jody Smith
1) Estrogen Avoidance Linked to Deaths of 50,000 Women. EmpowHER.
2) Sarrel, Philip et al. The Mortality Toll of Estrogen Avoidance AmerJPublicHealth 2013;103:1583-1588.
3) Jordan VC, Ford LG. Paradoxical clinical effect of estrogen on breast cancer risk: A “new” biology of estrogen-induced apoptosis. Cancer Prev Res 2011; 4(5):633-637.
4) Chlebowski RT, Anderson GL. Changing Concepts: Menopausal Hormone Therapy and Breast Cancer.JNatlCancerInst. 2012:104:517-527.
5) Manson, J. E. MD, DrPH, Chlebowski, R. T. MD; Stefanick, M, L. PhD; et al. Menopausal Hormone Therapy and Health Outcomes During the Intervention and Extended Poststopping Phases of the Women’s Health Initiative Randomized Trials. JAMA. 2013;310(13):1353-1368. doi:10.1001/jama.2013.278040